Why do I have condensation on my ceiling and how do I fix it?

B
bruce chambers
Updated: Nov. 5, 2021

My house was insulated in 1984 and when built, the construction company ran the batts across the stud wall and into the soffit, so no soffit air would enter the roof cavity. I removed the batts from the soffit, including the portion over the exterior stud wall when I installed larger soffit vents to ventilate the roof cavity. I now get condensation inside along the roof where the corner of the ceiling wall and interior wall line meet the which I suspect is due to the cold air penetrating at the roof line.

Can I solve thiis but reinstalling batts over the stud wall line when I replace my soffit? I plan to open up the entire length of the soffit (likely aluminum installation) and use the full vent soffit panels for the entire length of the roof so that I can maximize airflow from the soffit towards the apex of my roof. I'll open up all the roof joist cavities when I do this so that air will upflow for the entire length of the room instead of adjacent to the soffit vents that I installed when I first corrected this problem. So far it has worked well as my outside temp and attic temp differential averages 22F, every summer. Thanks. 

Responses (5)

bruce chambers
bruce chambers 2 years ago

CHI, believe zone 5. Plan to replace batts over stud wall from soffit side and place full width baffles over the insulation so baffle holds the insulation in place creating double thermal barrier and leaving most of soffit open to promote max air flow to vent attic. Plan is to replace wood soffit and spaced vented screens with continuous max soffit vent to promote max air flow. Pitch of room and volume of insulation within attic is too much to do this job from inside. Thx, will read wat you sent too. 

Mike Reynolds 2 years ago

Hope it helps Bruce. It sounds like you understand what went wrong and how to fix it. 

bruce chambers
bruce chambers 2 years ago

Update Jan 2022 / opened soffits and replaced missing insulation over the stud wall and placed a rafter vent between each truss on both sides of the house which solved the problem. Zero condensation now at temps of -10F. 

Mike Reynolds 2 years ago

Great stuff Bruce, glad to hear it worked out!